1. Field of the Invention
The present invention relates to a surround surveillance system. In particular, the present invention relates to a surround surveillance system for a mobile body which is preferably used for surround surveillance of a car, a train, etc., for human and cargo transportation. Furthermore, the present invention relates to a mobile body (a car, a train, etc.) which uses the surround surveillance system.
2. Description of the Related Art
In recent years, an increase in traffic accidents has become a major social problem. In particular, in a crossroad or the like, various accidents may sometimes occur. For example, people rush out into the street in which cars are travelling, a car collides head-on or into the rear of another car, etc. It is believed, in general, that such accidents are caused because a field of view for drivers and pedestrians is limited in the crossroad area, and many of the drivers and pedestrians do not pay attention to their surroundings and cannot quickly recognize dangers. Thus, improvement in a car itself, arousal of attention of drivers, improvement and maintenance of traffic environment, etc., are highly demanded.
Conventionally, for the purpose of improving traffic environment, mirrors are installed at appropriate positions in a crossroad area such that the drivers and pedestrians can see blind areas behind obstacles. However, the amount of blind area which can be covered by a mirror is limited and, furthermore, a sufficient number of mirrors have not been installed.
In recent years, many large motor vehicles, such as buses and some passenger cars, have a surveillance system for checking the safety therearound, especially at a rear side of the vehicle. The system includes a surveillance camera installed in the rear of the vehicle, and a monitor provided near a driver""s seat or on a dashboard. The monitor is connected to the surveillance camera via a cable. An image obtained by the surveillance camera is displayed on the monitor. However, even with such a surveillance system, the driver must check the safety at both sides of the vehicle mainly by his/her own eyes. Accordingly, in a crossroad area or the like, in which there are blind areas because of obstacles, the driver sometimes cannot quickly recognize dangers. Furthermore, a camera of this type has a limited field of view so that the camera can detect obstacles and anticipate the danger of collision only in one direction. In order to check the presence/absence of obstacles and anticipate the danger of collision over a wide range, a certain manipulation, e.g., alteration of a camera angle, is required.
Since a primary purpose of the conventional surround surveillance system for motor vehicles is surveillance in one direction, a plurality of cameras are required for watching a 360xc2x0 area around a motor vehicle; i.e., it is necessary to provide four or more cameras such that each of front, rear, left, and right sides of the vehicle is provided with at least one camera.
Also, the monitor of the surveillance system must be installed at a position such that the driver can easily see the screen of the monitor from the driver""s seat at a frontal portion of the interior of the vehicle. Thus, positions at which the monitor can be installed are limited.
In recent years, vehicle location display systems (car navigation systems) for displaying the position of a vehicle by utilizing a global positioning system (GPS) or the like have been widespread, and the number of cars which has a display device has been increasing. Thus, if a vehicle has a surveillance camera system and a car navigation system, a monitor of the surveillance camera system and a display device of the car navigation system occupy a large area and, hence, narrow the space around the driver""s seat because they are separately provided. In many cases, it is impossible to install both the monitor and the display device at a position such that the driver can easily see the screen of the monitor from the driver""s seat. Furthermore, it is troublesome to manipulate two systems at one time.
As a matter of course, in the case of using a motor vehicle, a driver is required to secure the safety around the motor vehicle. For example, when the driver starts to drive, the driver has to check the safety at the right, left, and rear sides of the motor vehicle, as well as the front side. Naturally, when the motor vehicle turns right or left, or when the driver parks the motor vehicle in a carport or drives the vehicle out of the carport, the driver has to check the safety around the motor vehicle. However, due to the shape and structure of the vehicle, there are driver""s blind areas, i.e., there are areas that the driver cannot see directly behind and/or around the vehicle, and it is difficult for the driver to check the safety in the driver""s blind areas. As a result, such blind areas impose a considerable burden on the driver.
Furthermore, in the case of using a conventional surround surveillance system, it is necessary to provide a plurality of cameras for checking the safety in a 360xc2x0 area around the vehicle. In such a case, the driver has to selectively switch the cameras from one to another, and/or turn the direction of the selected camera according to circumstances, in order to check the safety around the vehicle. Such a manipulation is a considerable burden for the driver.
According to one aspect of the present invention, a surround surveillance system mounted on a mobile body for surveying surroundings around the mobile body includes an omniazimuth visual system, the omniazimuth visual system including: at least one omniazimuth visual sensor including an optical system capable of obtaining an image of 360xc2x0 view field area therearound and capable of central projection transformation for the image, and an imaging section for converting the image obtained by the optical system into first image data; an image processor for transforming the first image data into second image data for a panoramic image and/or for a perspective image; a display section for displaying the panoramic image and/or the perspective image based on the second image data; and a display control section for selecting and controlling the panoramic image and/or the perspective image.
In one embodiment of the present invention, the display section displays the panoramic image and the perspective image at one time, or the display section selectively displays one of the panoramic image and the perspective image.
In another embodiment of the present invention, the display section simultaneously displays at least frontal, left, and right view field perspective images within the 360xc2x0 view field area based on the second image data.
In still another embodiment of the present invention, the display control section selects one of the frontal, left, and right view field perspective images displayed by the display section; the image processor vertically/horizontally moves or scales-up/scales-down the view field perspective image selected by the display control section according to an external operation; and the display section displays the moved or scaled-up/scaled-down image.
In still another embodiment of the present invention, the display section includes a location display section for displaying a mobile body location image; and the display control section switches the display section between an image showing surroundings of the mobile body and the mobile body location image.
In still another embodiment of the present invention, the mobile body is a motor vehicle.
In still another embodiment of the present invention, the at least one omniazimuth visual sensor is placed on a roof of the motor vehicle.
In still another embodiment of the present invention, the at least one omniazimuth visual sensor includes first and second omniazimuth visual sensors; the first omniazimuth visual sensor is placed on a front bumper of the motor vehicle; and the second omniazimuth visual sensor is placed on a rear bumper of the motor vehicle.
In still another embodiment of the present invention, the first omniazimuth visual sensor is placed on a left or right corner of the front bumper; and the second omniazimuth visual sensor is placed at a diagonal position on the rear bumper with respect to the first omniazimuth visual sensor.
In still another embodiment of the present invention, the mobile body is a train.
In still another embodiment of the present invention, the surround surveillance system further includes: means for determining a distance between the mobile body and an object around the mobile body, a relative velocity of the object with respect to the mobile body, and a moving direction of the object based on a signal of the image data from the at least one omniazimuth visual sensor and a velocity signal from the mobile body; and alarming means for producing alarming information when the object comes into a predetermined area around the mobile body.
According to another aspect of the present invention, a surround surveillance system includes: an omniazimuth visual sensor including an optical system capable of obtaining an image of 360xc2x0 view field area therearound and capable of central projection transformation for the image, and an imaging section for converting the image obtained by the optical system into first image data; an image processor for transforming the first image data into second image data for a panoramic image and/or for a perspective image; a display section for displaying the panoramic image and/or the perspective image based on the second image data; and a display control section for selecting and controlling the panoramic image and/or the perspective image.
According to still another aspect of the present invention, a mobile body includes the surround surveillance system according to the second aspect of the present invention.
According to still another aspect of the present invention, a motor vehicle includes the surround surveillance system according to the second aspect of the present invention.
According to still another aspect of the present invention, a train includes the surround surveillance system according to the second aspect of the present invention.
In the present specification, the phrase xe2x80x9can optical system is capable of central projection transformationxe2x80x9d means that an imaging device is capable of acquiring an image which corresponds to an image seen from one of a plurality of focal points of an optical system.
Hereinafter, functions of the present invention will be described.
A surround surveillance system according to the present invention uses, as a part of an omniazimuth visual sensor, an optical system which is capable of obtaining an image of 360xc2x0 view field area around a mobile body and capable of central projection transformation for the image. An image obtained by such an optical system is converted into first image data by an imaging section, and the first image data is transformed into a panoramic or perspective image, thereby obtaining second image data. The second image data is displayed on the display section. Selection of image and the size of the selected image are controlled by the display selection section. With such a structure of the present invention, a driver can check the safety around the mobile body without switching a plurality of cameras or changing the direction of the camera as in the conventional vehicle surveillance apparatus, the primary purpose of which is surveillance in one direction.
For example, an omniazimuth visual sensor(s) is placed on a roof or on a front or rear bumper of an automobile, whereby driver""s blind areas can be readily watched. Alternatively, the surround surveillance system according to the present invention can be applied not only to automobiles but also to trains.
The display section can display a panoramic image and a perspective image at one time, or selectively display one of the panoramic image and the perspective image. Alternatively, among frontal, rear, left, and right view field perspective images, the display section can display at least frontal, left, and right view field perspective images at one time. When necessary, the display section displays the rear view field perspective image. Furthermore, the display control section may select one image, and the selected image may be vertically/horizontally moved (pan/tilt movement) or scaled-up/scaled-down by an image processor according to an external key operation. In this way, an image to be displayed can be selected, and the display direction and the size of the selected image can be freely selected/controlled. Thus, the driver can easily check the safety around the mobile body.
The surround surveillance system further includes a location display section which displays the location of the mobile body (vehicle) on a map screen using a GPS or the like. The display control section enables the selective display of an image showing surroundings of the mobile body and a location display of the mobile body. With such an arrangement, the space around the driver""s seat is not narrowed, and manipulation is not complicated; i.e., problems of the conventional system are avoided.
The surround surveillance system further includes means for determining a distance from an object around the mobile body, the relative velocity of the mobile body, a moving direction of the mobile body, etc., which are determined based on an image signal from the omniazimuth visual sensor and a velocity signal from the mobile body. The surround surveillance system further includes means for producing alarming information when the object comes into a predetermined distance area around the mobile body. With such an arrangement, a safety check can be readily performed.
Thus, the invention described herein makes possible the advantages of (1) providing a surround surveillance system for readily observing surroundings of a mobile body in order to reduce a driver""s burden and improve the safety around the mobile body and (2) providing a mobile body (a vehicle, a train, etc.) including the surround surveillance system.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.